Cable actuators are known comprising a screw/nut assembly, the screw of which is rotated by an electric motor, and the nut of which is mobile in translation. The mobile element is coupled to one or more cables, in order to exert traction on the cables.
A cable actuator of this type is known from document FR2809464, wherein the element in translation is the screw, whereas the nut is mobile in translation under the action of a motor. The cable passes into a bore in the screw, and is coupled by means of a tolerant fastener to the misalignments of the cable.
In certain applications, in particular in robotic applications, the size of the actuator is highly critical, and it is important to ensure that this size is as small as possible.
Cable actuators are known comprising a screw which is fitted such as to rotate, and is driven by an electric motor, with a nut cooperating with the screw and being associated with anti-rotation means, such that rotation of the screw under the action of the motor gives rise to axial displacement of the nut, and two parallel cables which are coupled to the nut on both sides of it.
For the same course, this device makes it possible to reduce the size of the cable actuator. In fact, in the known cable actuators, in which the cable(s) is/are coupled to the screw which is displaced, the screw is designed to extend from both sides of the actuator. Thus, the general size would be at least 2C+L, where C is the course of the actuator, and L is the size of the nut. In the actuator according to the invention, this minimum size is now only C+L.